The ADs describe their working day
A typical day for the Day Shift will start with a Toolbox Meeting in the Conference Room at 11:30am.
After the Toolbox we will make our way to the Doghouse for a Handover from the Night shift. This will consist of the drillers having a separate Handover in regards to the hole and how it’s drilling.
The ADs (Assistant Drillers) will handover if there’s any Equipment Isolations or Permits to Work open and if so describe the nature of the work. The Night Shift will also inform us of any maintenance they have performed on equipment or breakdowns they have encountered.
So during drilling operations the ADs will carry out maintenance, mix mud and generally help out anyone requiring assistance in between core runs.
Our main areas of responsibility are to mix mud, operate the PDPH (Pipedeck Pipehandler) and TFM (Tubular Feeding Machine) and Tool Handling when recovering core samples.
Using the sophisticated mud system on board we, at request of the driller, have various viscosity muds readily available depending on the ground the driller is coring through. This product clears waste material, called “cuttings” away, or is used to stabilize the hole.
“Mud” is a mixture of fresh water and a clay product called Bentonite or other additives depending on the type of drilling in progress. It is mixed with fresh water to increase dispersion into any unstable layers. We can also change the viscosity. So a thicker mud is used for sand layers where the ground is less stable where a thinner mix would simply disperse into the ground providing no support. We measure the viscosity using a beaker and funnel, timing how long it takes to reach a certain level.
We are drilling through clay layers and the hole is stable so sea water is being pumped down the “String” to clear the cuttings away. The drill pipe in the hole is referred to as the “String”.
So far maintenance-wise the ADs have checked that the mud pumps are running smoothly and the mud stored in the tanks is agitated so as the product does not separate.
We will be performing a Derrick sweep later in the day to make sure systems housed within are all functioning. This consists of greasing sheaves, physically checking fixings and secondary retentions and checking for corrosion to the structure. Also a good time to take in the stunning views of the Gulf.
We now await the arrival of a fresh core sample to be winched up where we will strip the core barrel, extract the sample and rebuild the barrel to send back for another core run.